The present invention relates to a method of and an apparatus for connecting two elements together, and in particular to a method of and an apparatus for magnetically holding two partially ferromagnetic elements together while they are being connected.
In the fiber optics industry, a recent push towards automation has forced manufacturers to rethink the standard products and processes, and consider other materials and methods that would make automation easier to implement. Conventionally, glue has been used to fix various elements used in fiber optics together. However, gluing can cause losses in signal strength, and is very difficult to automate. Therefore, the effectiveness of other attaching methods has been explored. One such alternative attaching method is welding. One of the major drawbacks with welding is that it is very difficult to align, hold and weld small elements with the precision required in the fiber optics field.
Some conventional welding machines use fork-shaped tools to hold the elements together while they are being welded. Unfortunately, these devices do not apply evenly distributed forces to the elements, which results in significant shifts during welding. This misalignment is compounded by any post-weld shift, which occurs when the molten metal contracts during solidification, resulting in the two surfaces being pulled together.
One method that has been developed in an attempt to overcome these problems is disclosed in U.S. Pat. No. 5,386,488 issued Jan. 31, 1995 in the name of Yoichi Oikawa. This method still uses a fork-shaped clamping tool to hold the elements during welding, but it overcomes some of the disadvantages of the prior art by placing a jig in between the clamping tool and one of the elements in an attempt to distribute the forces more evenly. The drawbacks in this invention include the need for a large number of welds to hold all the elements together, and the need for the specially designed jig. Each welding step could cause a minor misalignment, which would require an extra realignment step. This delay would greatly increase the cost and time of manufacture for each part. Similarly, the manufacture and application of the jig will also greatly increase the manufacturing time and cost.
An object of the present invention is to overcome the shortcomings of the prior art by providing a connecting apparatus that applies a relatively evenly distributed force, and a connecting method that does not require any additional fixing steps.
Accordingly, the present invention relates to a method of connecting two elements together, comprising the steps of:
securing a first element, having a first ferromagnetic connecting portion, in a first holding means;
securing a second element, having a second ferromagnetic connecting portion, in a second holding means, at least one of the first and second holding means being movable to adjust the relative position of the first and second elements;
aligning the first element with the second element by moving at least one of the first and second holding means relative to the other to position the first and second elements into a desired alignment;
magnetizing one of the first or second ferromagnetic connecting portions to attract the other of the first or second ferromagnetic connecting portions thereto;
releasing the element with the other ferromagnetic connecting portion from its holding means, whereby magnetic attraction between the first and second ferromagnetic connecting portions hold the first and second elements together; and
fixing the first and second elements together.
Another aspect of the present invention relates to an apparatus for connecting two elements together, comprising:
a first holding means for securing a first element therein, the first element having a first ferromagnetic connecting portion;
a second holding means for securing a second element therein, the second element having a second ferromagnetic connecting portion, at least one of the first and second holding means being movable relative to the other;
aligning means for moving at least one of the first and second holding means relative to the other to position the first and second elements into a desired alignment;
magnetizing means for magnetizing one of the first or second ferromagnetic connecting portions, whereby the other of the first or second ferromagnetic connecting portions is attracted thereto; and
fixing means for fixing the first element to the second element;
whereby, when the aligning means moves the two elements into alignment, the magnetizing means is; activated, the element with the other of the first or second ferromagnetic connecting portion is released from its holding means, and magnetic attraction between the first and second ferromagnetic connecting portions hold the first and second elements together while the fixing means fixes the two elements together.